First of all, thanks to both of you.
What Brian says is what I did. Here you can see an example:
Local: Access code 9 | begins with 22[2-5] | number of digits 9, so the dial pattern is 922[2-5]xxxxxx
And this works well for everyone, but the secretary has a button (on the 7962G) that when pressed would call the last incoming call. Finding out, I knew this was configured by a colleague who is no longer with our company, I contacted him and does not remember how or where did this configuration, but it did in the UC500. so I'm looking for that on the web